Molinia caerulea, known by the common name purple moor-grass, is a species of grass that is native to Europe, west Asia, and north Africa. It grows in locations from the lowlands up to 2,300 m (7,546 ft) in the Alps. Like most grasses, it grows best in acid soils, ideally pH values of between 3.5 and 5, however, it can continue to live under more extreme conditions, sometimes to as low as 2. It is common on moist heathland, bogs and moorland throughout Britain and Ireland. Introduced populations exist in northeastern and northwestern North America. The specific epithet caerulea means "deep blue" and refers to the purple spikelets.